Hybrid and electric vehicles include high voltage battery packs that provide power to a fraction motor to propel the vehicle when operating in an electric mode. The traction battery may also be used to power various vehicle systems and components, such as power steering and electrical accessories, for example. The traction battery contains one or more arrays of battery cells that are interconnected to reach a desired voltage to meet the energy demands of the vehicle. Bus bars are used to connect the battery cells together. For instance, to connect a pair of cells, the terminals of the pair of cells are attached to a bus bar secured with corresponding fasteners or welded in place. The voltages of the battery cells are monitored by an associated battery control module that balances the charge for each cell or pair of cells and controls battery charging, discharging, and conditioning in cooperation with a vehicle system controller. Various applications include a separate and independent voltage sensor or sensing lead/wire connected to each battery cell or pair of cells so that the battery control module can control and balance the charge for each cell or cell pair. The cell voltage sensing leads are secured to the terminal post by an associated nut or other fastener.